Reenginer RedisModulesClient to enable Read from replica, Write to master

[ivanfrias]

Due to the high volume of reads, we need to diverge read operations to replicas.

We have created a ReadOnlyConnectionProvider that is injected into JedisSentineled. This provider has logic to understand if we are receiving a Search-type command.

The RedisModulesClient is responsible for initializing a Jedis client, based on the existing configuration. The only issue with this is that the getUnifiedJedis method is private and we can't extend it. We are currently copying class behaviour into our version of it, but this raises the question on how to keep track of change to the base class ( especially patches ).

We'd like to know if there are plans to enable overriding this class so clients can override it ( like we are doing).
Enabling this would bring Jedis closer to other libs like Lettuce in terms of feature-parity.